Seminar: Multiscale Modeling of Heterogeneous Granular Systems Alberto M. Cuitiño Mechanical and Aerospace Engineering Rutgers University Piscataway, New Jersey [email protected] IHPC-IMS Program on Advances & Mathematical Issues in Large Scale.

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Transcript Seminar: Multiscale Modeling of Heterogeneous Granular Systems Alberto M. Cuitiño Mechanical and Aerospace Engineering Rutgers University Piscataway, New Jersey [email protected] IHPC-IMS Program on Advances & Mathematical Issues in Large Scale.

Seminar:
Multiscale Modeling of Heterogeneous
Granular Systems
Alberto M. Cuitiño
Mechanical and Aerospace Engineering
Rutgers University
Piscataway, New Jersey
[email protected]
IHPC-IMS Program on
Advances & Mathematical Issues
in Large Scale Simulation
(Dec 2002 - Mar 2003 & Oct - Nov 2003)
Institute of High Performance Computing
Institute for Mathematical Sciences, NUS
Collaborators
• Gustavo Gioia
• Shanfu Zheng
Singapore 2003
cuitiño@rutgers
Rutgers
1.
2.
3.
4.
5.
6.
7.
8.
9.
Harvard University
William and Mary
Yale University
Princeton University
Columbia University
University of Pennsylvania
Brown University
Rutgers University (1766)
Dartmouth
Rutgers
University
RU
Singapore 2003
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Rutgers
Rutgers
University
Newark
New Brunswick
Camden
NYC
Philadelphia
Singapore 2003
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College
Ave
Livignston
Busch
Douglass
Cook
Rutgers,
New Brunswick
Singapore 2003
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Hairston Leads Rutgers Past Navy 48-27
SEPTEMBER 27, 2003
Golf
Stadiumand Engineering
Science
Rutgers,
Busch
Singapore 2003
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Design
and
Dynamics
Thermal
Sciences
Fluid
Mechanics
Solids,
Materials
and Structures
Haym
Benaroya
Haim
Baruh
Zhixiong
(James) Guo
Doyle
D. Knight
William
Bottega
Hae
Chang
Gea
Yogesh
Jaluria
Michael
R.
Muller
Alberto
Cuitiño
Noshir
A.
Langrana
Constantine
E. Polymeropoulos
Timothy
Wei
Mitch
Denda
Constantinos
Mavroidis
Kyung
T. Rhee
Abdelfattah
M.G.
Zebib
Entrance
Ellis
Dill M.
Madara
Ogot
Stephen
D.Zabusky
Tse
Norman
J.
Andrew
Norris
DajunShan
Zhang
Jerry
Rutgers,
Engineering
Assimina
S. Bachi Pelegri
Kook
Pae
Tobias
Rossman
George Weng
Singapore 2003
Rutgers,
Mechanical and Aerospace
cuitiño@rutgers
Current Research
•
•
•
•
•
•
•
•
Granular Systems (G. Gioia and S. Zheng)
Crystal Plasticity
Multiscale Modeling
Foam Mechanics
Folding of Thin Films
Microelectronics
Digital Image Correlation
Computational Material Design
(Ferroelectric Polymers)
Singapore 2003
Support from NSF, DOE, DARPA, FAA, NJCST, IFPRI, CAFT
is gratefully acknowledged
cuitiño@rutgers
Damage due to Electromigration
in Interconnect Lines
Sequence of pictures showing void
and hillock formation in an 8µm wide
Al interconnect due to
electromigration
(current density 2x107 A/cm²,
temperature 230°C)
Thomas Göbel (t.goebel@ifw-dresden .de), 18.04.02
Singapore 2003
cuitiño@rutgers
E  0, s = 0
V
Schimschak and
Krug, 2000
T
Schimschak and
Krug, 2000
Singapore 2003
cuitiño@rutgers
Grain Boundary Effects
VOID MOTION
@ GRAIN BOUNDARY
Initial Defect
Grain 1
Grain 2
VOID RELEASE
From GRAIN BOUNDARY
VOID TRAPPING
by GRAIN BOUNDARY
Atkinson and Cuitino ‘03
Singapore 2003
ecuitiño@rutgers
Goal
Load
Understand and quantitatively
predict the MACROSCOPIC
behavior of powder systems under
compressive loading based on
MICROSCOPIC properties such
as particle/granule behavior and
spatial arrangement
Need for MULTISCALE Study
Singapore 2003
PARTICLES
(discrete)
POWDERS
(continuum)
cuitiño@rutgers
Background
Macroscopic
Compaction Curve
Compaction Force
1
3rd Stage
.9
0
Relative Density
.8
0
.7
0
1st Stage
.6
0
2nd Stage
.5
0
0th Stage
.4-4
0
0
1
-3
0
1
-2
0
1
-1
0
1
e
rc
o
nF
tio
c
a
p
m
o
dC
e
liz
a
rm
o
N
Singapore 2003
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Stages
Mixing
Die Filling
Large Deformation
Singapore 2003
Rearrangement
Localized Deformation
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Identifying Processes and
Regimes
Mixing
Discharge
Transport
Die Filling
Granulation
Vibration
Early
Consolidation
Consolidation
Precompression
Compact
Formation
Characteristics:
Characteristics:
Characteristics:
Characteristics:
Characteristics:
• Large relative
motion of particles
• Large relative
motion of particles
• Limited relative
motion of particles
• No relative
motion of particles
• No relative
motion of particles
• Differential
acceleration
between particles
• Differential
acceleration
between particles
• Low particle
acceleration
•Low acceleration
• Low acceleration
• Same neighbors
• Same neighbors
• Large number of
distinct neighbors
• Large number of
distinct neighbors
•Quasi-static
•Quasi-static
• Low forces among
particles
• Low forces
among particles
• Sizable forces
among particles
• Large forces
among particles
• Long times,
relatively slow
process
• Short times
•Small particle
deformation
(elastic + plastic)
• Large particle
deformation
• Transient
• Same neighbors
• Quasi-static
• Low forces
among particles
• Small particle
deformation
(elastic)
• Quasi steady state
Singapore 2003
cuitiño@rutgers
Identifying Numerical Tools
(which can use direct input from finer scale)
Early
Consolidation
Mixing
Discharge
Transport
Die Filling
Granulation
Vibration
Precompression
PD/DEM/MC
PD/DEM/MC
PD/DEM/MC
Consolidation
Compact
Formation
GCC
GQC
Ballistic
Deposition
Numerical tools
appropriate for process
Singapore 2003
OUR SCOPE
cuitiño@rutgers
Identifying Numerical Tools
(which can use direct input from finer scale)
Early
Consolidation
Mixing
Discharge
Transport
Die Filling
Granulation
Vibration
Precompression
PD/DEM/MC
PD/DEM/MC
PD/DEM/MC
Consolidation
Compact
Formation
GCC
GQC
Ballistic
Deposition
Numerical tools
appropriate for process
Singapore 2003
OUR SCOPE
cuitiño@rutgers
Die Filling
Cohesion
Open Configuration
Numerical
Experimental
Singapore 2003
No Cohesion
Dense Configuration
Numerical
Experimental
cuitiño@rutgers
Identifying Numerical Tools
(which can use direct input from finer scale)
Early
Consolidation
Mixing
Discharge
Transport
Die Filling
Granulation
Vibration
Precompression
PD/DEM/MC
PD/DEM/MC
PD/DEM/MC
Consolidation
Compact
Formation
GCC
GQC
Ballistic
Deposition
Numerical tools
appropriate for process
Singapore 2003
OUR SCOPE
cuitiño@rutgers
Rearrangement
Process by which open structures collapse into dense configurations
• Cohesive Powders are susceptible to rearrangement while
• Non-Cohesive Powders are not
X-Ray Tomography-Density Maps
Al2O3 Granules. Diameter = 30 microns
Lannutti, 1997
Punch
Video Imaging
Glass Beads, Diameter = 1.2 mm
Gioia and Cuitino, 1999
Increasing Pressure
Singapore 2003
Increasing Pressure
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A physical description
Convexification implies
coexistence of two phases
Energy landscape exhibits a Spinoidal
Structure (nonconvex)
Total
H
H
Singapore 2003
H
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A relaxation mechanism
Particle Rearrangement Mechanism
Snap-Through of Rings (Kuhn et al. 1991)
Ring Structures in Cohesive Powders
Numerical
Experimental
Singapore 2003
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Relaxation process
Numerical
Experimental
Singapore 2003
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Experiments and Theory
Experimental
Theoretical
Kong et al., 1999
Al2O3
Singapore 2003
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2D: simulation and experiment
Singapore 2003
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Rearrangement Front
Experiment
Singapore 2003
Simulation
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“Grains”
Singapore 2003
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2D Simulations (Size Distribution)
Singapore 2003
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3D Simulations
Singapore 2003
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Comparison with Experiment
Mueth, Jaeger,
Nagel 2000
Singapore 2003
Experiment
Simulation
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Further Predictions
Experiment
Singapore 2003
Simulation
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Particle Rearrangement 3D
• Homogeneous
particle size;
• r = 0.5 mm;
r = 0.5mm
• Particles =
120,991
Singapore 2003
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Quantitative Predictions
(a)
 = 0.627
0.65
•Rearrangement front;

0.6
u=7.5
u=5.0
u=2.5
 =0.51
0.5
0.45
•Density increase;
u=9.1
0.55
0
10
20
30
40
50
(b)
1
•Contact number
increase;
u=7.5
0.5
u=5.0
u=2.5
u=0.25
0
0
10
20
30
40
50
(c)
1
u=9.1
h / 
•Relative movement
stops;
v / 
u=9.1
0.5
u=2.5
u=5.0
u=7.5
u=0.25
0
0
(d)
10
6.5
20
30
40
Nc = 6.27
u=9.1
6
Nc
50
u=0.25
5.5
5
u=7.5
4.5
4
Singapore 2003
0
u=5.0
10
20
u=2.5
30
40
50
cuitiño@rutgers
Heterogeneous System
(Same Material)
•Log-normal distribution; d = 2.16 ~ 9.10 mm; particles=13,134
Without rearrangement
Singapore 2003
After rearrangement
cuitiño@rutgers
Multiphase Systems
Singapore 2003
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Identifying Numerical Tools
(which can use direct input from finer scale)
Early
Consolidation
Mixing
Discharge
Transport
Die Filling
Granulation
Vibration
Precompression
PD/DEM/MC
PD/DEM/MC
PD/DEM/MC
Consolidation
Compact
Formation
GCC
GQC
Ballistic
Deposition
Numerical tools
appropriate for process
Singapore 2003
OUR SCOPE
cuitiño@rutgers
Granular Quasi-Continuum
FEM Mesh
Set of Particles
Constrain kinematics of the particles by overimposing a
displacement field described by a set of the displacements in a
set of points (nodes) and a corresponding set of interpolation
functions (a FEM mesh)
Singapore 2003
Combined System
A quasi-continuum
approach
cuitiño@rutgers
Governing Equations
P
PVW
Euler
Equation
P
8m 2P 8n 2Vm
1
mn
î
w
2
+
P
m
f áî u m = 0
8m 2P
1dî wmn
m
+ f = 0
mn
8n 2Vm 2 dr
P
Local Equilibrium
Singapore 2003
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Force Fields
• Plastic deformation
follows similarity solution;
Contacts on each particle
are independent.
• Volume change after
inter-particle voids are
filled in.
-1200
volume
changed
r2
d
-800
 = r1 + r2 - d
-600
Hertzian
contact
-400
-200
Similarity solution
0
Singapore 2003
r1
-1000
Force
• Elastic contact follows
Hertz contact law;
0
0.1
0.2
Indentation ()
0.3
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Role of FF parameters - sy
1
• Effect of yielding stress is
significant;
• Solidification force differ
significantly but the
solidification density
relative unchange.
sy = 0.1
0.9
Density (g/cm3)
• Lower sy yield higher
deformation under the
same pressure and thus
higher density;
sy = 0.01
sy = 1 (in MPa)
0.8
HDPE 100
E = 1 GPa
n=3
 = 0.3
0 = 1.1 g/cm3
0.7
0.6
0.5
0
Singapore 2003
2
4
6
Force (kN)
8
10
cuitiño@rutgers
Role of FF parameters:
hardening
1
• Soft material (n) is
easy to be solidified.
0.9
Density (g/cm3)
• Effect of hardening
parameter n is
significant;
n=
n = 10
0.8
HDPE 100
E = 1 GPa
n=3
sy = 1 MPa
 = 0.3
0 = 1.1 g/cm3
0.7
0.6
0.5
0
Singapore 2003
2
4
6
Force (kN)
8
10
cuitiño@rutgers
Role of FF parameters:
Poisson’s ratio
1
 = 0.2
Density (g/cm3)
0.9
 = 0.3
0.8
HDPE 100
E = 1 GPa
sy = 1 MPa
n=3
0 = 1.1 g/cm3
0.7
0.6
0.5
0
Singapore 2003
2
4
6
Force (kN)
8
10
cuitiño@rutgers
Case of Study: Multiphase System
Singapore 2003
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Spatial Distribution
Phase I
Phase I
Phase I
Variant 1
Variant 2
Variant 3
Singapore 2003
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Spatial Distribution
Phase II
Variant 1-4
Singapore 2003
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Spatial Distribution
Phase III
Needs an uniform
distribution
Singapore 2003
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Multiphase System
Rearrangement
Full mixed +
Cohesion force
Singapore 2003
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Multiphase System
Post-Rearrangement
Input for GQC
Singapore 2003
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Calibration of FF
Detergent Granule 1
1.5
1.4
Density (g/cc)
1.3
1.2
1.1
Sample:
mass = 0.75 g
size = 1212 6.6 (red)
1212 5.8 (blue)
density = 0.789 g/cc (red)
0.898 g/cc (blue)
Particles:
size = 0.216 ~ 0.91 mm
number = 13,134
1
0.9
0.8
0.7
0.6
0.5
0
Singapore 2003
1
2
3
4
stress (MPa)
5
6
7
cuitiño@rutgers
Multiphase System
Comparison with Experiment
MACROSCOPIC Behavior
• At early stage of experiment
the deformation is the
mainly from the particle
rearrangement.
1.2
density (g/cc)
• Density diversity at initial
state is mainly due to the
irregular shape of real
particles;
1.3
1.1
1
0.9
Sample :
mass = 0.075 (g)
3
size = 55 3.3 (mm )
density = 0.91 (g/cc)
particle size = 0.1~0.5 (mm)
particles = 7,986
0.8
0.7
0.6
Singapore 2003
0
0.5
1
1.5
2
stress (MPa)
2.5
3
cuitiño@rutgers
Multiphase System:
density evolution
Full Field Predictions
Z
dens: 0.68 0.78 0.87 0.97 1.06 1.16 1.25 1.35
X
Y
6
Z
4
2
0
0
0
2
Movie Here
2
4
Y
4
6
6
8
8
10
Singapore 2003
X
10
cuitiño@rutgers
Multiphase System:
pressure evolution
Z
X
Y
6
Z
4
2
0
0
Movie Here
0
2
2
4
Y
4
6
6
8
8
10
Singapore 2003
X
10
cuitiño@rutgers
Granular Quasi-Continuum
GOOD
• Allows for explicit account
of the particle level
response on the effective
behavior of the powder
• Provides estimates of
global fields such as
stress, strain density
• Is numerically efficient, can
also be improved by using
stochastic integration
• Provides variable spatial
resolution
Singapore 2003
BAD
• Is not well posed to
handle large nonaffine motion of
particles
• Particle deformation is
only considered in an
approximate manner
(as in PD/DEM)
cuitiño@rutgers
Towards Computationally Aided
Material Design
ACCEPTABLE RANGE OF
NANOCOMPOSITE PARAMETERS
ACCEPATLE MAXIMUM PORE SIZE
FORCE PARAMETERS
NANO COMPOSITE
PARAMETERS
PORE SIZE
ACCEPTABLE
RANGE OF FORCE PARAMTERS
TO NANO SCALE
Singapore 2003
MICRO SCALE
cuitiño@rutgers
Summary and conclusions
• Powder compaction is a complex process where many dissimilar
entities (particles) consolidate by various concurrent mechanisms.
• In the low pressure regime, rearrangement and localized particle
deformation dominates the mechanical response.
• In this initial regime, compaction proceeds in a discontinuous fashion
by an advancing front.
• The physics of the rearrangement can be traced to a spinoidal
structure in the energy density of the system.
• This process can be theoretically described using the framework of
non-convex analysis.
• The effect of particle deformability and die wall roughness are
incorporated into the analysis in a clear and physical manner.
• Numerical simulations verify the theoretical model
• Experimental studies validate the model and simulations
• 3D simulations show a similar behavior that 2D ones, indicating the
same physics operates in 2D and 3D cases.
Singapore 2003
cuitiño@rutgers